APRIL
45 1
NOTES
1957
the corresponding nitrile (IV); the nitrile (IV) and formatioqa could not be brought about through the the acid (V) have previously been reported by conventional halogenation of the acyl group with Hager and Starkey.2 The method of BlickeS with subsequent condensation with a n amino compound. The melting point of the ethyl DL-dipalmitoxyCHZCOOH I CHZCN CH2Br pantothenate thus prepared was 61.5-63.0’ in comparison with 57.0-58.5’ for the same compound prepared by the in situ palmitoylation of ethyl I I I I F F F F DL-pantothenate.2 Upon single dose assay with I1 111 IV V rats,4 the newly synthesized ethyl DL-dipalmitoxypantothenate was found to be fully active as a source of pantothenic acid. 1. i-C&MgCl 1. AcCl EXPERIMENTAL
Ethyl ~~N-In,r-dipalmitoxy-p,p’-dimethylbutyryl] paminopropionate (ethyl DL-dipalmitoxypantothenate). Slx hundred twenty-five milligrams (1 mmole) of DL-dipalmitoxypantoic acid2 was dissolved in 40 ml. of dry pyridine which contained 200 mg. (excess) of ethyl p-alanate and 208 mg. (1 mmole) of dicyclohexyl carbodiimide. The clear mixture was set aside a t room temperature for 96 hr. The precipitate was removed by filtration, and the filtrate was evaporated t o dryness under reduced pressure. The residue was taken up into ether, and washed with I N hydrochloric acid, a cold 57, potassium carbonate solution and with
2. CH,O 3. Hydrolysis
R=
